Autoerythrocyte sensitization causes painful bruises, usually on the arms or legs.
Autoerythrocyte sensitization is rare. It typically occurs in white women who are experiencing emotional stress.
Doctors are not sure of the cause. The disorder was named because of an unproven theory that the body somehow becomes sensitive (allergic) to its own red blood cells (erythrocytes). That is, red blood cells that escape from the blood vessels may cause an allergic-type reaction that leads to the bruising. However, most doctors feel that the bruising is simply due to self-inflicted injury since most affected people are under emotional stress or also have symptoms of mental disorders.
People develop episodes of painful bruising. Bruises may develop spontaneously or after injury or surgery. Bruising can occur on different sites of the body from where the injury occurs. Bruises then resolve after a few days. Bruises never occur on those parts of the body that cannot easy be reached by the person, such as the back.
Doctors first do tests of the blood clotting system to determine whether a blood clotting disorder is causing the bruising. Results of these tests are normal in people with autoerythrocyte sensitization.
Bruises resolve on their own. Some people benefit from treatment that helps them deal with emotional stress.
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